Biomedical Engineering – From Theory to Applications

A Mechanical Cell Model and Its Application to Cellular Biomechanics
of the CSKs of a randomly oriented model at a cell deformation (D) of 0, 10, and 20 µm.
The CSKs at D = 0 µm were distributed uniformly over all angles. With elongation of the
cell, the distribution of the orientation angle of the CSK became skewed towards 0° (Fig.
11), demonstrating that the CSKs tend to become passively aligned in the stretched
direction. This passive re-alignment gradually increased the elastic resistance of the
whole cell against the stretched direction, causing the load-deformation curve to be nonlinear
(Fig. 9).
(a) (b) (c)
Probability P θ
0.3
0.2
0.1
0
0 30 60 90
CSK orientation angle
θ (deg)
Probability P θ
0.3
0.2
0.1
0
0 30 60 90
CSK orientation angle
θ (deg)
Probability P θ
0.3
0.2
0.1
0
0 30 60 90
CSK orientation angle
θ (deg)
Fig. 11. Histogram of the existence probability of the orientation angles Pθ of the CSK the
randomly oriented model during a cell deformation (D) value of (a) 0, (b) 10, and (c)
20 µm.
Not all the CSKs were stretched as the cell elongated. Figure 12 shows a histogram of
stretch ratios Pλ of the CSK of the randomly oriented model at a deformation D of 0, 10, and
(a) (b)
Probability P λ
(c)
Probability P λ
1.0
0.8
0.6
0.4
0.2
0
1.0
0.8
0.6
0.4
0.2
0
CSK stretch ratio λ
CSK stretch ratio λ
Probability P λ
1.0
0.8
0.6
0.4
0.2
0
CSK stretch ratio λ
Fig. 12. Histogram of the stretch ratio Pλ of the CSK of the randomly oriented model at a cell
deformation (D) value of (a) 0, (b) 10, and (c) 20 µm.
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